Packing-ring.



H. KELLER.

PACKING RING.

TION man JULY .APPLICA 9,19l8- 1,326,064. Patented Dec. 23,1919.

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HULDREICH KELLER, OE ZURICH, SWITZERLAND, ASSIGNOR T0 AKTIENGESELLSGHAFTDER MASCHINENFABRIKEN ESGHER WYSS 8600., OF ZURICH, SWITZERLAND.

PACKING-RING.

Specification of Letters Patent.

Patented Dec. 23, 1919.

Application filed July 9, 1918. Serial N 0. 244,101.

Z '0 all whom it may concern:

Be it known that I, I-IULDREIOH KELLER, a citizen of the Republicof'Switzerland, residing at Zurich, 'Hardturmstrasse 19, Switzerland,have-invented certainnew and useful Improvements in Packing-Rings;

and I do hereby declare the following to be .a clear, full, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying drawing, and to letters or figures of referencemarked thereon, which form a part of this specification.

The present invention. has reference to improvements in packing ringsfor horizontal shafts and relates more particularly to improved meansfor balancing or equalizing the gravity of such rings. The inventionspecifically consists in theprovisionof at least one recess in the innercircumferential surface of the ring, the recess being open toward thehigh pressure side and closed toward the low pressure side if the recessis above the shaft and closed toward the high pressure side and opentoward the low pressure side if the recess is below the shaft. 7

The counterbalancing arrangement can be so made, that the cylindricalinternal surface of the ring is provided with a recess at its top sideand a recess at its bottom side, the former being open toward the highpressure side and closed toward the low and the latter being open towardthe low pres sure side and closed toward the high pressure side.

. Packing rings for horizontal shafts, such as are found in steamturbines and the like, are required to readily adapt themselves to theposition of the shaft, so that they are freely supported thereon orfloat, as; the saying is. But such rings, owing'to the gravity action,have the tendency to cling to the shaft, remaining thereby in continuousoperative contact with it, and in consequence unduly wearing out. Theresult is a steadily increasing leakage with all its troubles.

As a remedy it has been proposed to support the packing ring by suitablyarranged steel springs; but such springs, when subjected for any lengthof time to the high temperatures found for instance in the high pressurechamber of a steam turbine, soon lose their initial elasticity andbecome useless for their purposes; besides which, they quickly rust andbreak.

The balanced packing ring according to the present invention,effectively obviates all these drawbacks and will keep in full operativefunction for an indefinite period.

An embodiment of the invention will now be described in detail inconnection with the accompanying drawing in which:

Figure 1 represents a vertical section through a constructional exampleof the improvement, as intended for use in a steam turbine;

Fig. 2 shows a fragmental vertical crosssection thereof, and Fig. 3represents a diagrammatic plan.

In Fig. 1 of the drawing the numeral 1 denotes a fragment of thepartition wall dividing a high pressure stage having a pressure p, fromthe succeeding stage having a lower pressure 79 of a steam turbine. Thecarbon packing ring 2 is divided along the horizontal plane and the twohalves are operatively held together by the circumferential spiralspring 3. The ring, under the steam pressure acting on it from the leftto the right (p -p is pressed against the inner surface of the partitionwall 1, so as to form a steam tight joint.

In order to counterbalance the gravity of the packing ring 2 with itsspring 3, two tongue-shaped recesses are provided within the innercircun'iference of the carbon ring symmetrically to the vertical middleplan :000 (Fig. 2). The upper recess 4 opens toward the left, that is tosay toward the high pressure chamber and is closed toward the lowpressure chamber by the wall-thickness A--B. The lower recess 5 is. opentoward the right, that is to say tothe lower pressure side, and isclosed toward the high pressure side by the wall-thickness CD. In theupper recess consequently approximately the full high pressure p, willobtain, and in the lower recess approximately the full lower pressure 39As shown diagrammatically in Fig. 3, the upper recess has thedotted-line shape EAF, and the lower recess the outline G-H-D, and thetwo recesses partly overlap to the extent of the cross-shaded portionsAK-DJA, with the result that the carbon ring will be acted on by a forcewhich is substantially equal to the product of the area AK-DJA, measuredin square centimeters, and the diflerence of the specific steampressures p and p measured in kilograms/square centimeters, thus wehave:

ring half, which open section is under full high pressure, and since anopen sectlon (recess 5) of the lower ring half is diametrically oppositeto the closed section AV B of the upper ring half, which recess 5 isunder full low pressure, it is obvious that the non-overlapping surfacesEJ DKFE and G-JA-KH-G exert persurface unit only about one half of thebalancing effort exerted by the overlap surface AJDK-A.

By properly dimensioning the recesses, the forces acting on the carbonring halves from within will equalize the gravity and thuscounterbalance the ring.

In case theweight of the ring is light and the difference between thespecific steam pressures p, and p, is considerable, then it suffices toprovide only one such recess. But in this instance a recess in the upperring half must face the high pressure chamber andmust be closed towardthe low pressure chamber, while a recess provided in the lower ring halfmust face the low pressure chamber and must be closed against the highpressure.

If, however, the weight of the parts to be counterbalanced isconsiderable, then it will be necessary to provide two oppositelydisposed recesses for correspondingly large dimensions, as shown by wayof example in the drawing.

The recesses may be also subdivided latorally, that is to say incircumferential direction, in suitable manner, for instanceby ribs orwebs.

What I claim is:

1. In packing rings for horizontal shafts, the arrangement forcounterbalancing the gravity of the ring comprising at least one recessin the inner circumferential surface of the ring, the recess being opentoward the high pressure side and closed toward the low pressureside ifthe recess is above the shaft and closed toward the high pressure sideand open toward the low pressure'side, if the recess is below the shaft,substantially as set forth.

2. In packing rings for horizontal shafts, the arrangement forcounterbalancing the gravity of the ring, comprising a recess at the topside and a recess at the bottom side of the cylindrical internal surfaceof the ring, the former recess being open toward the high pressure sideand closed toward the low pressure side andthelatter recess being opentoward the low pressure side and closed toward the high pressure side,substantially as set forth.

3. In packing rings for horizontal shafts,

the arrangement for counterbalaneing the gravity of the ring, comprisinga subdivided ring, spring means for holding-the ring together, the ringhaving at least one pressure recess in its cylindrical internal surfaceto one side of its horizontal axial plane, this recess being open towardthe high pressure side and closed towardjthe low pressure side if it isabove the shaft, and closed toward the high pressureside and open towardthe low pressure side if it is below the shaft, substantially as setforth.

4. In packing rings for horizontal shafts, the arrangement forcounterbalancing the gravity of the ring comprising a'subdivided ring,spring means for holding'thering together, a recess at the top side anda re cess at the bottom side of the cylindrical internal surface of thering, the-former recess being open toward the high pressure side andclosed toward the low pressure side and the latter recess beingopentoward the low pressure side and closed toward the high pressureside, substantially as set forth.

5. In packing rings for horizontal shafts, the arrangement forcounterbalaneing the gravity of the ring, comprising one or morerecesses situated to one side of the horizontal middle plane of thering, said recesses being in the inner circumferential-surface of thering and open at one of the pressure sides of the ring and closed to theother pressure side, said recesses when positioned above the shaft beingclosed to the low pressure, and when below the shaft being closed to thehigh pressure side.

In testimony that I claim the foregoing as my invention I have signed myname.

HULDREICH KELLER.

